The present system relates to medical devices, and more particularly, to gastric port systems for delivery of materials to the interior of a body cavity.
Patients for which normal ingestion of food becomes difficult or impossible may require placement of a feeding tube to assist in providing their nutritional needs. For some individuals, such as comatose patients, stroke victims, or those with a compromised gastrointestinal tract and the like, this may require placement of a tube that is introduced percutaneously into the stomach for delivery of nutritional products directly into the stomach or jejunum. The procedure, known as a Percutaneous Endoscopic Gastrostomy (PEG), involves the introduction of an endoscope into the stomach. The desired site where the stoma is to be created is indicated from above by depressing the abdomen and viewing the depressed site with the endoscope. Transillumination may also be utilized to locate the desired site through the abdominal wall. A sheathed needle or trocar punctures the abdominal wall and enters the stomach, creating a stoma. The needle is removed and a looped insertion wire is introduced through the sheath where it is grasped by a snare or forceps deployed from the working channel of the endoscope. Once it is captured, the insertion wire is pulled into the working channel of the endoscope. The endoscope is then withdrawn from the patient via the oral cavity, pulling the insertion wire with it.
In the standard Ponsky method (or “pull” method), the distal loop of a percutaneous gastrostomy feeding tube is coupled to the insertion wire loop exiting the patient's mouth. With the insertion wire now tethered to the gastrostomy feeding tube, the endoscopist retracts the portion of the insertion wire exiting the stoma, thereby pulling the gastrostomy feeding tube into the patient's mouth and towards the stomach. With continued retraction of the insertion wire, the distal end of the gastrostomy feeding tube is pulled out through the stoma. The gastrostomy feeding tube typically includes a tapered dilator portion to aid its passage through the stoma. Once the feeding tube has been properly positioned with the proximal end cap or bolster of the feeding tube against the internal wall of the stomach, it is secured by an external bolster positioned against the outside of the abdomen wall.
In a variation of the PEG procedure known as the “push” method, the gastrostomy feeding tube is advanced or pushed down the esophagus by the physician and into position in the stomach using a wire guide that has been placed in the same manner as the insertion wire in the “pull” method. More specifically, the feeding tube is loaded on the portion of the wire guide exiting the patient's mouth by passing the end of the wire guide through a lumen extending through the length of the feeding tube. While holding the wire guide stationary, the physician pushes the feeding tube along the wire guide through the patient's mouth, into the stomach, and then out through the stoma. The feeding tube is then secured in the same manner as the “pull” method.
Yet another method is simply to insert the feeding tube through the patient's abdominal wall and bypass insertion through the mouth. However, this method typically requires the attachment of a bolster to the interior portion of the feeding tube, which may need to be delivered and attached endoscopically. Alternatively, when the device has a low profile, it may be inserted using the Seldinger technique.
As stated above, typically, a retention bolster is positioned against the inside and/or outside of the abdomen wall, or whichever body cavity or area the gastric port is being used in relation to. The bolster is present to keep in place and support the gastric port and prevent sudden or unexpected removal of the port from the stoma site. Bolsters for supporting ports, such as feeding tubes, inside or outside the body have generally focused on maintaining the secure anchoring of the device to the patient. To provide support, bolsters have employed flanges, cross-bars, discs, or balloons for contacting the surface of the tissue. In the past, however, bolsters have tended to increase the localized pressure at the exit site, especially when the port, either accidentally or intentionally, is moved thereabout.
One particular application exhibiting the deficiencies of existing bolsters involves the use of PEG tubes to provide long term access to the stomach. A PEG tube is often maintained at its stoma site by an internal and external retention bolster for several months while the PEG tube is used to provide access to the stomach. Existing bolsters, however, remain inflexibly clamped to the feeding tube so as to maintain the catheter in position during use. As a consequence, these bolsters do not accommodate the unavoidable movements of the port during extended periods of time or, for example, the loss or gain of weight of the patient subsequent to introduction of the port.
A need therefore exists for an improved retention bolster for use adjacent to a body surface to support a gastric port.